I've been using an insulin pump for many years now. You will probably need a prescription from your doctor, but my pump, the consumables and the insulin are all covered by the basic insurance (LAMAL), minus of course the normal deductibles.
My pump (Medtronic) is paid through a leasing process, so I pay a regular rate every 3 months which covers the cost of the pump and consumables, which I have to order directly with Medtronic. I don't think you can get the consumables in a pharmacy. I've found the customer service at Medtronic to be good and efficient. The phone calls are answered promptly without long waits. The consumables take about 5 working days to be delivered, as they all come from a warehouse in the Netherlands, though if there's an emergency they have a small local stock which can be delivered overnight.